Urban history is littered with the dead bodies of scrapped public transit projects. When eager commuters and car companies turned the automobile into the most popular form of transit in the world in the twentieth century, many cities set aside plans for expanding their public transit systems, such as the electric tram system planned for regions feeding into Melbourne, Australia. In some cases, city planners actually ripped out existing transit systems like Los Angeles' once-enormous cable car network. What would these cities and others look like if their public transit systems had continued to thrive and we lived in a world without cars? We've got five alternate urban histories of public transport for you below.

Right now, the city of Baltimore is considering upgrading its mass transit to include aerial gondolas, a system of elevated trams on cables with a tiny carbon footprint. They would initially service mostly the convention center and waterfront areas, but could branch out all over the city. Apparently gondola-makers have recently seen a spike in requests for mass transit systems, and even New York City is considering an aerial gondola to take commuters from Manhattan to Governor's Island and on to Brooklyn. Here is what the proposed gondolas might look like on a typical Baltimore city street (original photo from Zaloudek.net).

Seattle has a long and tragic history with monorails, once believed to be the public transit of the future. Just recently, the city voted to expand its tiny, largely-decorative monorail system, built for the World's Fair back in the 1960s. But urban planners have been trying to make Seattle a monorail city since 1910, when a Seattle monorail was first proposed (and shelved). We have yet to see whether the city will act on this latest vote for the monorail, but this is what you might see in downtown Seattle (original photo by GiSuser) if the system started ferrying commuters.

If you've ever visited San Francisco, you know that the downtown area is dominated by a wide street called Market (original photo by Hyku). What you probably don't know is that Market is actually a gushing river that early city planners decided to bury underground just to make everything nicer for carriages — and, later, cars. If we'd built San Francisco to cooperate with the region's actual geography, downtown San Francisco might have a system of canals like the ones in Venice (original photo by Minnaert). People could boat to work instead of burning gas in their cars.